"No Comment"
Politicians, rockstars, royalty and other celebrities seem to favour the "no comment" line of defence over any other. But have you ever thought of why this is? Surely, flat-out denial must be the best defence?
Well, no, actually. The thing is, with today's legal system, the "No Comment" comment is in fact a protection from the press on several different levels.
Keeping quiet
If someone who has been presented with incriminating evidence against themselves - or even just a nasty rumour - fails to say anything at all, or fails to respond to the press when they query the matter, the press is fully in their right to run the story, and say that "Bill Gates was unavailable for comment". If the rumour is hot enough, a comment from mr. Gates is entirely unnecessary for the story to stand, and the newspaper is legally entitled to run the story as they please, if some source or other backs it up.
Denial
If someone denies an allegation - guess what? The newspapers suddenly have a license to print the rumours! "Elton John denied today that he likes to fantasize about the queen while having anal sex", "David Beckham denies to have hired prostitutes on a regular basis while his girlfriend was pregnant with their first-born child", and "Tony Blair denies that he enjoys a line of cocaine every now and then, but only in good company" make fantastic stories, and the fact that the celebrities deny the allegations don't matter: The fact that the allegations are there means that someone must have thought them to be true, and hence, in the view of the majority of the public (especially the type of public that is likely to read tabloid newspapers in the first place), can seriously shift public opinion on somebody.
The quirk here is that if a journalist were to make up a story titled any of the above, and the victim of the made-up story denies it, then legally, the newspaper can run the story as much as they like, as they technically say what the celebrity didn't do - which is perfectly fine.
"No Comment"
Hence, no comment. When a journalist is faced with a celebrity saying "no comment", they have to print that the celeb refuses to comment - but that also means that they are walking a juridical quagmire if they decide to run the story, as running unconfirmed stories like this without trustworthy sources is a recipe for libel suits galore.